The present invention relates generally to circuit breakers. More specifically, the present invention relates to a remotely operated circuit breaker module for attachment to the side of a circuit breaker to provide remote actuation of the circuit breaker.
Remote operated circuit breaker modules (remote modules) are frequently combined with circuit breakers and panel mounted in control panel systems to provide remote operated circuit breakers. Remote operation of circuit breakers, e.g., opening, closing or resetting, are often desirable to perform such functions as service, diagnostics, load shedding, and power distribution, in areas that are unsafe or difficult to access.
Remote modules may be either a side mounted type, which mounts to the side of a standard circuit breaker housing, or a top mounted type, which mounts over the circuit breakers top, i.e., front face.
However, space is a premium in enclosures of control panel systems and prior art top mounted motor modules disproportionately increase the overall depth required of an enclosure in order to accommodate the remote module/circuit breaker assembly. That is, when the top mounted remote module is mounted to the panel of a control panel system, the circuit breaker is cantilevered off of the back of the remote module and extends deep into the enclosure by a distance equal to the combined height of the remote module and circuit beaker. Use of the top mounted remote module will often interfere with existing components in the enclosure, e.g., the system bus bar. Additionally, the cantilevered circuit breaker puts added stress on the remote module and often requires extra support blocks to prevent damage. This is especially problematic in the case of multi-pole circuit breakers or circuit breakers having heavy gauge wires.
Typically, remote modules of the side-mounted type are operatively connected to a circuit breaker with one or more poles associated therewith to form a remote operated circuit breaker assembly. The remote operated circuit breaker assembly is typically use to provide protection for a circuit having one or more phases. Alternatively, the remote module may also be used to remotely operate a plurality of circuit breakers stacked together, each protecting a separate circuit, which are required to be actuated simultaneously.
The circuit breakers of the above described prior art remote operated circuit breaker assembly typically include left and right half shells forming a split case enclosure which encloses the interior components of a pole of the circuit breaker. A circuit breaker with multiple poles will have an enclosure for each pole stacked together to form the circuit breaker. Each pole includes a circuit breaker actuator link having a handle extending out of the top of each enclosure, which is pivotally mounted to the interior of each enclosure. A handle tie kit passes through a hole located in the upper portion of each handle to operatively tie the handles together and to provide actuation of all the poles substantially simultaneously. Load and line (or source) terminals extend through opposing end portions of the bottom of each enclosure and are spaced to align with load and line bus bars of a typical control panel system respectively.
The prior art side mounted remote module of the above described remote operated circuit breaker assembly typically includes a module housing, which is open on one side, and a module motor disposed in the module housing. The open side of the module housing abuts against one of the outer half-shells of the circuit breaker and is fastened thereto to enclose the motor therein. That is, the outside surface of either the left or right half shell of the circuit breaker is stacked against the module housing to function as the inside surface of the enclosure for the prior art remote module. A module actuator is operatively associated with the module motor and includes a module handle which extends out of the top of the remote module. The handle tie kit also passes through a hole located in the upper portion of the module handle to operatively tie the module handle to the circuit breaker handles and to provide remote actuation of the circuit breaker. An electrical terminal, for providing power to the remote module, extends through an end portion of the bottom of the remote module substantially in line with either the line or load terminals of the circuit breaker poles.
However, because the prior art module housing must rely on the left or right half shell of the circuit breaker to form an enclosure, prior art side mounted remote modules can only be mounted on one side of the circuit breaker and must be hard fastened, e.g., riveted, to the circuit breaker at the factory. Additionally, the prior art remote modules cannot be utilized as stand alone retrofit kits for installation to existing circuit breakers in the field. Therefore, any retrofitting to remotely operated circuit breakers in the field would involve removal and replacement of existing manually operated circuit breakers.
Also, the prior art remote module handle actuates each pole of the circuit breaker by applying a torsional pressure to the circuit breaker handles through the handle tie kit at substantially a single point, i.e., the through hole in the upper portion of each handle. However, the torsion on the handle tie kit results in an actuation lag between the farthest (far pole) and nearest poles (near pole) relative to the remote module. That is the pole farthest from the remote module will close last when remotely actuated. This causes greater arcing on the contacts of the far pole with respect to the near pole, resulting in a respectively greater rate of ware to the contacts of the far pole. The actuation lag becomes more pronounce as the number of poles involved increases.
Additionally, because the electrical terminal of the prior art remote module extends out of the bottom of its enclosure substantially in line with the load or line terminals, the electrical terminal of the remote module often interferes with the load or line bus bars of a typical control panel system. This requires notches to be cut in the bus bars, thus resulting in an increased cost and a reduced current carrying capacity of the bus bars.
Accordingly, there is a need for an improved remote operated circuit breaker module for attachment to the side of a circuit breaker.
In an exemplary embodiment of the present invention a remote operated circuit breaker assembly is presented comprising at least one circuit breaker, a remote module for remotely operating the circuit breaker and an actuator tie pin. Each circuit breaker includes a circuit breaker enclosure of generally rectangular shape having one side and an opposing side, and a circuit breaker actuator link pivotally mounted inside the circuit breaker enclosure. The remote module includes a module housing mounted to the one side of the circuit breaker enclosure and having a shape generally congruent with the circuit breaker enclosure. A motor is disposed in the module housing, a module actuator is pivotally mounted inside the module housing and a coupling means couples the motor to the module actuator. The actuator tie pin connects the circuit breaker actuator link to the module actuator within the interior of the circuit breaker enclosure and the module housing. The actuator tie pin is received in aligned slots defined by the abutting circuit breaker enclosure side and module housing side.
In an alternative embodiment of the invention, the circuit breaker enclosure of the remote operated circuit breaker also has a top and the circuit breaker actuator link has a circuit breaker handle extending out of the top of the circuit breaker enclosure. An upper portion of the circuit breaker handle has a handle hole disposed therethrough. The module housing of the remote module has a top and the module actuator has a module handle extending out of the top of the module housing. An upper portion of the module handle has a module hole disposed therethrough. A handle tie kit, which passes through the handle hole and the module hole, operatively ties the handles together.
In another alternative embodiment of the invention, the remote operated circuit breaker also includes a limit switch. The limit switch has a limit switch actuator with a closed position for enabling rotation of the motor in a first direction and an open position for enabling rotation of the motor in an opposing second direction. The closed and open positions have a predetermined distance therebetween. Additionally, a limit switch lever is selectively located at a first position for retaining the limit switch actuator in the closed position, and is selectively located at a second position for retaining the limit switch actuator in the open position.